How to repair or replaceThe purpose and function of a
VSS -
In short
The Honda Speed Sensor's main purpose is to transmit speed
data to the TCU. It is reading the frequency of a bobbin that is attached to upper casing that speeds past the solid
state sensor. The bobbin is a cylindrical or spool-shaped coil
or insulated wire, usually containing a core of soft iron
which becomes magnetic when the wire is traversed by an
electrical current. The faster the wheel spins, the faster the
frequency the wheel magnet moves past the sensor thus the
higher speed reading on your speedometer. The vehicle speed
sensor counts the revolutions of the transmission output shaft. For a
given vehicle, the Transmission Control Module considers a certain number of
revolutions to equal a mile. A defective speed sensor can either
set off the "S" light or fail to engage the cruise
control, which also can affect other system controls. The result is that the
TCU thinks the vehicle is running at zero speed from what itís actually doing.
The
first thing most customers notice is a transmission error code
or intermittent reading on the speedometer which reset the
error code after
every ignition cycle.

SCHEMATIC

The first step is to check the
connection for any deformation, corrosion or other visible
signs of connection damage. The next step is to jack up the car and take voltage
readings (5V) pulses at the connector when the front wheel is
turn by hand. If no pulses are found, confirm input voltages
then inspect the inside of the VSS.
Unplug the VSS and remove the 10-mm bolt(s.) Remove by
lifting and twisting the unit upward.

LOCATION

Figure
1

Remove the VSS's two
screws and gently lift the top off for inspection. Caution:
DO NOT allow the spring to fall.

OVERHAUL

Figure
2

Inspect for signs of wear
between the conducting rod and the conducting surface. The rod
can be rounded off with a 400 grit sandpaper. The conducting
surface can be treated the same way.
Note: Add conducting grease to the treated areas
when done.